@article{1077473989,
author = {Gustin, William},
title = {Sets of finite planar order},
journal = {Duke Math. J.},
volume = {14},
number = {1},
year = {1947},
pages = { 51-66},
language = {en},
url = {http://dml.mathdoc.fr/item/1077473989}
}
Gustin, William. Sets of finite planar order. Duke Math. J., Tome 14 (1947) no. 1, pp. 51-66. http://gdmltest.u-ga.fr/item/1077473989/